Income Taxes (Schedule of Effective Income Tax Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Tax at statutory rate	$ 46,600	$ 47,015	$ 50,595
Change in federal income tax rate	0	0	(110,508)
State income taxes, net of federal tax benefits	8,575	8,098	4,943
Non-deductible meals and entertainment	1,117	1,044	1,495
Income tax credits	(1,600)	(1,800)	(1,780)
Equity compensation	(207)	(312)	(820)
Other, net	477	1,688	(2,257)
Total income tax expense (benefit)	$ 54,962	$ 55,733	$ (58,332)

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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